'use strict';

hexo.extend.helper.register('list_archives', function (options = {}) {

  const {
    config
  } = this;
  const archiveDir = config.archive_dir;
  const {
    timezone
  } = config;
  const lang = this.page.lang || this.page.language || config.language;
  let {
    format
  } = options;
  const type = options.type || 'monthly';
  const {
    style = 'list', transform, separator = ', '
  } = options;
  const showCount = Object.prototype.hasOwnProperty.call(options, 'show_count') ? options.show_count : true;
  const className = options.class || 'archive';
  const order = options.order || -1;
  const limit = 8;
  let result = '';

  var more_button
  if (lang === 'zh-CN') {
    more_button = '查看更多';
  } else if (lang === 'zh-TW') {
    more_button = '查看更多';
  } else {
    more_button = 'More';
  }


  if (!format) {
    format = type === 'monthly' ? 'MMMM YYYY' : 'YYYY';
  }

  const posts = this.site.posts.sort('date', order);
  if (!posts.length) return result;

  const data = [];
  let length = 0;

  posts.forEach(post => {
    // Clone the date object to avoid pollution
    let date = post.date.clone();

    if (timezone) date = date.tz(timezone);
    if (lang) date = date.locale(lang);

    const year = date.year();
    const month = date.month() + 1;
    const name = date.format(format);
    const lastData = data[length - 1];

    if (!lastData || lastData.name !== name) {
      length = data.push({
        name,
        year,
        month,
        count: 1
      });
    } else {
      lastData.count++;
    }
  });

  const link = item => {
    let url = `${archiveDir}/${item.year}/`;

    if (type === 'monthly') {
      if (item.month < 10) url += '0';
      url += `${item.month}/`;
    }

    return this.url_for(url);
  };

  if (style === 'list') {
    result += `<ul class="${className}-list">`;

    for (let i = 0, len = data.length; i < Math.min(len, limit); i++) {
      const item = data[i];

      result += `<li class="${className}-list-item">`;

      result += `<a class="${className}-list-link" href="${link(item)}">`;
      result += transform ? transform(item.name) : item.name;


      if (showCount) {
        result += `<span class="${className}-list-count">${item.count}</span>`;
      }
      result += '</a>';
      result += '</li>';

    }

    if (data.length > limit) {
      result += `<li class="${className}-list-item">`;
      result += `<a class="${className}-list-link is_center" href="` + '/' + `${archiveDir}" >`;
      result += more_button;
      result += '</a>';
      result += '</li>';
    }
    result += '</ul>';
  } else {
    for (let i = 0, len = data.length; i < Math.min(len, limit); i++) {
      const item = data[i];

      if (i) result += separator;

      result += `<a class="${className}-link" href="${link(item)}">`;
      result += transform ? transform(item.name) : item.name;

      if (showCount) {
        result += `<span class="${className}-count">${item.count}</span>`;
      }

      result += '</a>';
    }
    if (data.length > limit) {
      result += `<a class="${className}-link" is_center" href="${archiveDir}" >`;
      result += more_button;
      result += '</a>';
    }

  }

  return result;
})